ASHRAE Research Project 1480 Report - Food Service Technology ...

Capture and Containment Testing
The capture and containment determinations were made in accordance with ASTM F 1704-05
Standard Test Method for Capture and Containment Performance of Commercial Kitchen
Exhaust Ventilation Systems. The standard clarifies the performance expectations by defining
some key terms. The phrase "hood capture and containment" is defined as “the ability of the
hood to capture and contain grease-laden cooking vapors, convective heat, and other products of
cooking processes”. Hood capture refers to the products getting into the hood reservoir from the
area under the hood, while containment refers to these products staying in the hood reservoir and
not spilling out into the space adjacent to the hood. The phrase "minimum capture and
containment " is defined as "the conditions of hood operation in which minimum exhaust flow
rates are just sufficient to capture and contain the products generated by the appliance in idle and
heavy-load cooking conditions, or at any intermediate prescribed load condition."
During the capture and containment tests, the exhaust flow rate was reduced until spillage of the
thermal plume was observed. The exhaust flow rate was then increased in fine increments until
full capture and containment was achieved for the given condition. The airflow rate at this
condition is referred to as the threshold exhaust airflow rate for complete capture and
containment, or threshold capture and containment rate. This airflow value is the lowest and
most repeatable airflow rate for making direct comparisons across various scenarios. The layout
of visualization systems for the capture and containment evaluation is shown in Figure 21.
Displacement MUA
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Displacement MUA
Figure 21. Layout of Visualization Systems for Hood Capture and Containment Performance
Evaluations
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RP-1480